ST. PETERSBURG, Fla. — Russian Tennis Federation President Shamil Tarpischev has been fined $25,000 by the WTA Tour and suspended from tour involvement for a year for questioning Serena and Venus Williams’ gender in comments on Russian television last week.

Tarpischev appeared on the Russian late-night show “Evening Urgant” alongside former WTA player Elena Dementieva last week. When Dementieva was asked what it was like to play against the Williams sisters, Tarpischev jumped in and referred to them as the “Williams brothers,” according to multiple reports.

After a back-and-forth with the show host and Dementieva, who did not laugh at the comment, Tarpischev reportedly continued: “It’s frightening when you look at them. But really you just need to play against the ball.”

The derogatory remarks by the head of the Russian Tennis Federation come out of nowhere and attacks not just two of the sport’s biggest stars, but the very foundation of the women’s game.

The WTA Tour said Friday that the $25,000 fine is the maximum allowed under tour rules and that it is seeking Tarpischev’s removal as chairman of the Kremlin Cup for one year. The tour also said Tarpischev owes the Williams sisters a personal apology.

“The statements made by Shamil Tarpischev on Russian television with respect to two of the greatest athletes in the history of women’s tennis are insulting, demeaning and have absolutely no place in our sport,” WTA Tour chairman and CEO Stacey Allaster said in a statement.

“Mr. Tarpischev’s statements questioning their genders tarnish our great game and two of our champions,” the statement continued. “His derogatory remarks deserve to be condemned and he will be sanctioned.”

Tarpischev said Saturday that his comments were only meant as jokes and he doesn’t understand why he was banned for a year by the WTA Tour.

Asked whether he regretted his comments, Tarpischev told The Associated Press at the Kremlin Cup that the program on which he spoke was “a humorous show,” adding: “I don’t answer stupid questions.”

Dave Haggerty, the president and chairman of the U.S. Tennis Association, also called on Tarpischev to issue a formal apology to the sisters.

“As the president of the Russian Tennis Federation and a member of the International Olympic Committee, Mr. Tarpischev is expected to conduct himself with the highest degree of integrity and sportsmanship,” Haggerty said in a statement. “Unfortunately, his comments do not embody either of these traits and in fact were reprehensible.”

Tennis great Martina Navratilova responded to the remarks in a text message to the New York Times: “Flippant or not, you cannot have an official making this kind of an offhand remark. I think it’s disgraceful, and there should be a serious sanction. This cannot be tolerated.”

In a statement released later Saturday by the Russian Tennis Federation, Tarpischev denied any “malicious intent” and said his quotes had been taken out of context.

“I didn’t want to offend any athlete with my words,” he said. “I regret that this joke … has garnered so much attention. I don’t think this incident deserves so much fuss.”

The Williams sisters are “outstanding athletes” who “personify strength and perseverance,” he added.

Russian Sports Minister Vitaly Mutko told the ITAR-Tass agency that he regretted that Tarpischev had made the comments and that his suspension was “an unpleasant fact,” but suggested his sanction should be reduced. “It’s probably worth trying to get the punishment softened,” Mutko said.

Tarpischev has been chairman of the Kremlin Cup, Russia’s only WTA event, for all of its 18 years as a women’s tour event, and is also a member of the International Olympic Committee. During the 1990s, he was the personal tennis coach to Russian President Boris Yeltsin and served as his adviser on sports matters.